1. |
- Bahlmann, Hans, 1973-
(författare)
-
Goal-directed fluid therapy during major abdominal surgery
- 2019
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Background: Both hypo- and hypervolemia increase the risk for postoperative complications after major abdominal surgery. Fluid needs vary amongst patients depending on differences in preoperative dehydration, intraoperative physiology and surgical characteristics. Goal-directed fluid therapy (GDFT) aims to target the right amount of fluid administration in each patient by evaluating the effect of fluid boluses on haemodynamic parameters such as stroke volume. It has been shown to reduce postoperative morbidity and is generally recommended for high-risk surgery. The overall aim of this thesis was to evaluate whether more simple devices for GDFT result in clinical benefit, thus facilitating the application of GDFT in more patients.Aim: To compare performance and clinical benefit of pleth variability index (PVI), a noninvasive, easy-to-use device for GDFT, with the reference method of oesophageal Doppler; to evaluate methods for measuring preoperative dehydration and its effect on fluid handling by the body; and to confirm the expected clinical benefits of GDFT in patients undergoing oesophageal resection, a high risk procedure.Methods: In Studies I-III 150 patients scheduled for open abdominal surgery of at least 2 hrs were randomised to GDFT with either PVI or oesophageal Doppler. In the first half of the cohort, both monitors were connected to compare intraoperative performance. In 30 patients preoperative dehydration was analysed. In study IV 64 patients undergoing oesophageal resection were randomised to GDFT using pulse contour analysis or standard treatment.Results: The concordance between PVI and oesophageal Doppler for indicating the need for and effect of a fluid bolus was low, and both had only limited capacity to predict the effect of a fluid bolus. Both methods resulted in comparable amounts of fluid being administered and similar clinical outcome. Preoperative dehydration was limited but did impact on fluid handling. Patients receiving GDFT during oesophageal resection received more fluid and more dobutamine compared to controls, but this did not result in any clinical benefit.Conclusions: There are methodological issues as well as uncertainties about the clinical benefit of GDFT. We cannot recommend a strict application of any GDFT strategy, but suggest that its components should be incorporated in a more encompassing assessment of a patient’s fluid needs. The measurement, impact and treatment of preoperative dehydration need to be further clarified.
|
|
2. |
- Biurrun, Idoia, et al.
(författare)
-
Benchmarking plant diversity of Palaearctic grasslands and other open habitats
- 2021
-
Ingår i: Journal of Vegetation Science. - Oxford : John Wiley & Sons. - 1100-9233 .- 1654-1103. ; 32:4
-
Tidskriftsartikel (refereegranskat)abstract
- Journal of Vegetation Science published by John Wiley & Sons Ltd on behalf of International Association for Vegetation Science.Aims: Understanding fine-grain diversity patterns across large spatial extents is fundamental for macroecological research and biodiversity conservation. Using the GrassPlot database, we provide benchmarks of fine-grain richness values of Palaearctic open habitats for vascular plants, bryophytes, lichens and complete vegetation (i.e., the sum of the former three groups). Location: Palaearctic biogeographic realm. Methods: We used 126,524 plots of eight standard grain sizes from the GrassPlot database: 0.0001, 0.001, 0.01, 0.1, 1, 10, 100 and 1,000 m2 and calculated the mean richness and standard deviations, as well as maximum, minimum, median, and first and third quartiles for each combination of grain size, taxonomic group, biome, region, vegetation type and phytosociological class. Results: Patterns of plant diversity in vegetation types and biomes differ across grain sizes and taxonomic groups. Overall, secondary (mostly semi-natural) grasslands and natural grasslands are the richest vegetation type. The open-access file ”GrassPlot Diversity Benchmarks” and the web tool “GrassPlot Diversity Explorer” are now available online (https://edgg.org/databases/GrasslandDiversityExplorer) and provide more insights into species richness patterns in the Palaearctic open habitats. Conclusions: The GrassPlot Diversity Benchmarks provide high-quality data on species richness in open habitat types across the Palaearctic. These benchmark data can be used in vegetation ecology, macroecology, biodiversity conservation and data quality checking. While the amount of data in the underlying GrassPlot database and their spatial coverage are smaller than in other extensive vegetation-plot databases, species recordings in GrassPlot are on average more complete, making it a valuable complementary data source in macroecology. © 2021 The Authors.
|
|
3. |
- Dengler, Juergen, et al.
(författare)
-
GrassPlot - a database of multi-scale plant diversity in Palaearctic grasslands
- 2018
-
Ingår i: Phytocoenologia. - : Schweizerbart. - 0340-269X. ; 48:3, s. 331-347
-
Tidskriftsartikel (refereegranskat)abstract
- GrassPlot is a collaborative vegetation-plot database organised by the Eurasian Dry Grassland Group (EDGG) and listed in the Global Index of Vegetation-Plot Databases (GIVD ID EU-00-003). GrassPlot collects plot records (releves) from grasslands and other open habitats of the Palaearctic biogeographic realm. It focuses on precisely delimited plots of eight standard grain sizes (0.0001; 0.001;... 1,000 m(2)) and on nested-plot series with at least four different grain sizes. The usage of GrassPlot is regulated through Bylaws that intend to balance the interests of data contributors and data users. The current version (v. 1.00) contains data for approximately 170,000 plots of different sizes and 2,800 nested-plot series. The key components are richness data and metadata. However, most included datasets also encompass compositional data. About 14,000 plots have near-complete records of terricolous bryophytes and lichens in addition to vascular plants. At present, GrassPlot contains data from 36 countries throughout the Palaearctic, spread across elevational gradients and major grassland types. GrassPlot with its multi-scale and multi-taxon focus complements the larger international vegetationplot databases, such as the European Vegetation Archive (EVA) and the global database " sPlot". Its main aim is to facilitate studies on the scale-and taxon-dependency of biodiversity patterns and drivers along macroecological gradients. GrassPlot is a dynamic database and will expand through new data collection coordinated by the elected Governing Board. We invite researchers with suitable data to join GrassPlot. Researchers with project ideas addressable with GrassPlot data are welcome to submit proposals to the Governing Board.
|
|
4. |
- Diaz, Sandra, et al.
(författare)
-
Pervasive human-driven decline of life on Earth points to the need for transformative change
- 2019
-
Ingår i: Science. - : American Association for the Advancement of Science (AAAS). - 0036-8075 .- 1095-9203. ; 366:6471
-
Forskningsöversikt (refereegranskat)abstract
- The human impact on life on Earth has increased sharply since the 1970s, driven by the demands of a growing population with rising average per capita income. Nature is currently supplying more materials than ever before, but this has come at the high cost of unprecedented global declines in the extent and integrity of ecosystems, distinctness of local ecological communities, abundance and number of wild species, and the number of local domesticated varieties. Such changes reduce vital benefits that people receive from nature and threaten the quality of life of future generations. Both the benefits of an expanding economy and the costs of reducing nature's benefits are unequally distributed. The fabric of life on which we all depend-nature and its contributions to people-is unravelling rapidly. Despite the severity of the threats and lack of enough progress in tackling them to date, opportunities exist to change future trajectories through transformative action. Such action must begin immediately, however, and address the root economic, social, and technological causes of nature's deterioration.
|
|
5. |
- Fa, John E., et al.
(författare)
-
Importance of Indigenous Peoples' lands for the conservation of Intact Forest Landscapes
- 2020
-
Ingår i: Frontiers in Ecology and the Environment. - : Wiley. - 1540-9295 .- 1540-9309. ; 18:3, s. 135-140
-
Tidskriftsartikel (refereegranskat)abstract
- Intact Forest Landscapes (IFLs) are critical strongholds for the environmental services that they provide, not least for their role in climate protection. On the basis of information about the distributions of IFLs and Indigenous Peoples' lands, we examined the importance of these areas for conserving the world's remaining intact forests. We determined that at least 36% of IFLs are within Indigenous Peoples' lands, making these areas crucial to the mitigation action needed to avoid catastrophic climate change. We also provide evidence that IFL loss rates have been considerably lower on Indigenous Peoples' lands than on other lands, although these forests are still vulnerable to clearing and other threats. World governments must recognize Indigenous Peoples' rights, including land tenure rights, to ensure that Indigenous Peoples play active roles in decision-making processes that affect IFLs on their lands. Such recognition is critical given the urgent need to reduce deforestation rates in the face of escalating climate change and global biodiversity loss.
|
|
6. |
- Garnett, Stephen T., et al.
(författare)
-
A spatial overview of the global importance of Indigenous lands for conservation
- 2018
-
Ingår i: Nature Sustainability. - : Springer Science and Business Media LLC. - 2398-9629. ; 1:7, s. 369-374
-
Tidskriftsartikel (refereegranskat)abstract
- Understanding the scale, location and nature conservation values of the lands over which Indigenous Peoples exercise traditional rights is central to implementation of several global conservation and climate agreements. However, spatial information on Indigenous lands has never been aggregated globally. Here, using publicly available geospatial resources, we show that Indigenous Peoples manage or have tenure rights over at least similar to 38 million km(2) in 87 countries or politically distinct areas on all inhabited continents. This represents over a quarter of the world's land surface, and intersects about 40% of all terrestrial protected areas and ecologically intact landscapes (for example, boreal and tropical primary forests, savannas and marshes). Our results add to growing evidence that recognizing Indigenous Peoples' rights to land, benefit sharing and institutions is essential to meeting local and global conservation goals. The geospatial analysis presented here indicates that collaborative partnerships involving conservation practitioners, Indigenous Peoples and governments would yield significant benefits for conservation of ecologically valuable landscapes, ecosystems and genes for future generations.
|
|
7. |
- Hill, Rosemary, et al.
(författare)
-
Nature's contributions to people: Weaving plural perspectives
- 2021
-
Ingår i: One Earth. - : Elsevier BV. - 2590-3330 .- 2590-3322. ; 4:7, s. 910-915
-
Tidskriftsartikel (refereegranskat)abstract
- “Nature's contributions to people” (NCP) is designed to provide space for the recognition of diverse and evolving culturally mediated ideas about what people derive from, and co-produce with, nature. Its origins, along with the IPBES conceptual framework in which it is embedded, is transdisciplinary, action-oriented, and inclusive and also embraces pluralism. NCP provides both generalizing and context-specific perspectives and analytical tools that can be interwoven and enables diverse actors to represent nature-people interactions for different scales, audiences, and decision-makers. NCP therefore can be used to understand and communicate the ways in which ongoing biodiversity decline may affect the complex relationships between people and nature. This Primer presents NCP in accessible language, highlights its unique contribution as a tool for plural valuation of nature in conservation assessments, clarifies common misconceptions, and provides examples of the innovative ways NCP has already been applied around the world.
|
|
8. |
- Hill, Rosemary, et al.
(författare)
-
Working with Indigenous, local and scientific knowledge in assessments of nature and nature's linkages with people
- 2020
-
Ingår i: Current Opinion in Environmental Sustainability. - : Elsevier BV. - 1877-3435 .- 1877-3443. ; 43, s. 8-20
-
Tidskriftsartikel (refereegranskat)abstract
- Working with indigenous and local knowledge (ILK) is vital for inclusive assessments of nature and nature's linkages with people. Indigenous peoples' concepts about what constitutes sustainability, for example, differ markedly from dominant sustainability discourses. The Intergovernmental Platform on Biodiversity and Ecosystems Services (IPBES) is promoting dialogue across different knowledge systems globally. In 2017, member states of IPBES adopted an ILK Approach including: procedures for assessments of nature and nature's linkages with people; a participatory mechanism; and institutional arrangements for including indigenous peoples and local communities. We present this Approach and analyse how it supports ILK in IPBES assessments through: respecting rights; supporting care and mutuality; strengthening communities and their knowledge systems; and supporting knowledge exchange. Customary institutions that ensure the integrity of ILK, effective empowering dialogues, and shared governance are among critical capacities that enable inclusion of diverse conceptualizations of sustainability in assessments.
|
|
9. |
- Kolosova, Valeria, et al.
(författare)
-
The bear in Eurasian plant names : motivations and models
- 2017
-
Ingår i: Journal of Ethnobiology and Ethnomedicine. - : BIOMED CENTRAL LTD. - 1746-4269. ; 13
-
Forskningsöversikt (refereegranskat)abstract
- Ethnolinguistic studies are important for understanding an ethnic group's ideas on the world, expressed in its language. Comparing corresponding aspects of such knowledge might help clarify problems of origin for certain concepts and words, e.g. whether they form common heritage, have an independent origin, are borrowings, or calques. The current study was conducted on the material in Slavonic, Baltic, Germanic, Romance, Finno-Ugrian, Turkic and Albanian languages. The bear was chosen as being a large, dangerous animal, important in traditional culture, whose name is widely reflected in folk plant names. The phytonyms for comparison were mostly obtained from dictionaries and other publications, and supplemented with data from databases, the co-authors' field data, and archival sources (dialect and folklore materials). More than 1200 phytonym use records (combinations of a local name and a meaning) for 364 plant and fungal taxa were recorded to help find out the reasoning behind bear-nomination in various languages, as well as differences and similarities between the patterns among them. Among the most common taxa with bear-related phytonyms were Arctostaphylos uva-ursi (L.) Spreng., Heracieum sphondylium L., Acanthus mollis L., and Allium ursinum L., with Latin loan translation contributing a high proportion of the phytonyms. Some plants have many and various bear-related phytonyms, while others have only one or two bear names. Features like form and/or surface generated the richest pool of names, while such features as colour seemed to provoke rather few associations with bears. The unevenness of bear phytonyms in the chosen languages was not related to the size of the language nor the present occurence of the Brown Bear in the region. However, this may, at least to certain extent, be related to the amount of the historical ethnolinguistic research done on the selected languages.
|
|
10. |
- Kovacs, Katalin T., et al.
(författare)
-
Change in autoantibody and cytokine responses during the evolution of neuromyelitis optica in patients with systemic lupus erythematosus : A preliminary study
- 2016
-
Ingår i: Multiple Sclerosis Journal. - : SAGE Publications. - 1352-4585 .- 1477-0970. ; 22:9, s. 1192-1201
-
Tidskriftsartikel (refereegranskat)abstract
- Background: Neuromyelitis optica (NMO)-systemic lupus erythematosus (SLE) association is a rare condition characterized by multiple autoantibodies. Objective: To examine if, during the evolution of NMO, anti-AQP4 responses are part of polyclonal B cell activation, and if T cell responses contribute. Methods: In 19 samples of six patients who developed NMO during SLE, we examined the correlation of AQP4-IgG1 and IgM with (i) anti-MOG IgG and IgM, (ii) anti-nuclear, anti-nucleosome and anti-dsDNA IgG antibodies, (iii) cytokines and chemokines in the serum and (iv) longitudinal relation to NMO relapses/remission. Results: AQP4-IgG1 was present 1-2-5 years before the first NMO relapse. During relapse, AQP4-IgG1, ANA, anti-dsDNA and anti-nucleosome antibodies were elevated. Anti-MOG IgG/IgM and AQP4-IgM antibodies were not detected. AQP4-IgG1 antibodies correlated with concentration of anti-nucleosome, IFN-γ,interferon-gamma-induced CCL10/IP-10 and CCL17/TARC (p
|
|
11. |
- Molnár, Bela, et al.
(författare)
-
Electrophysiologically-Active Maize Volatiles Attract Gravid Female European Corn Borer, Ostrinia nubilalis
- 2015
-
Ingår i: Journal of Chemical Ecology. - : Springer Science and Business Media LLC. - 0098-0331 .- 1573-1561. ; 41, s. 997-1005
-
Tidskriftsartikel (refereegranskat)abstract
- The European corn borer (ECB) is an important pest of maize in the northern hemisphere, but no reliable techniques exist for monitoring females during their reproductive period. In this study, we aimed to identify host-plant volatiles used by gravid Z-strain females in search for oviposition sites. Headspace of maize plants, to which gravid females orientated in a wind tunnel, was collected, and physiologically-active components were identified by using gas chromatography (GC) coupled with electroantennographic detection followed by GC-mass spectrometry. The antennae of female moths consistently responded to two maize volatiles, nonanal and decanal. Although these compounds are individually not characteristic for maize, a synthetic mix in a ratio found in maize headspace, 1:2.4 at 1 mu g mu l(-1) induced source contact and landing responses similar to maize plants in the wind tunnel. However, fewer females took flight in response to the mix, and those that took flight did so with an increased latency. To our knowledge, this is the first blend of host-plant volatiles that has been found to be physiologically active and to be able to induce attraction of gravid ECB females under laboratory conditions. Future tests will evaluate the attractiveness of the blend to the E-strain of ECB, the attractiveness of the blend in the field, and its potential in monitoring ECB populations.
|
|
12. |
- Molnar, Tihamer, et al.
(författare)
-
Severe fatigue and memory impairment are associated with lower serum level of anti-SARS-CoV-2 antibodies in patients with Post-COVID symptoms
- 2021
-
Ingår i: Journal of Clinical Medicine. - : MDPI. - 2077-0383. ; 10:19, s. 4337-4337
-
Tidskriftsartikel (refereegranskat)abstract
- Background: Post-COVID manifestation is defined as persistent symptoms or long-term complications beyond 4 weeks from disease onset. Fatigue and memory impairment are common post-COVID symptoms. We aimed to explore associations between the timeline and severity of post-COVID fatigue and anti-SARS-CoV-2 antibodies.Methods: Fatigue and memory impairment were assessed in a total of 101 post-COVID subjects using the Chalder fatigue scale (CFQ-11) and a visual analogue scale. Using the bimodal scoring system generated from CFQ-11, a score ≥4 was defined as severe fatigue. Serum anti-SARS-CoV-2 spike (anti-S-Ig) and nucleocapsid (anti-NC-Ig) antibodies were examined at two time points: 4-12 weeks after onset of symptoms, and beyond 12 weeks.Results: The serum level of anti-S-Ig was significantly higher in patients with non-severe fatigue compared to those with severe fatigue at 4-12 weeks (p = 0.006) and beyond 12 weeks (p = 0.016). The serum level of anti-NC-Ig remained high in patients with non-severe fatigue at both time points. In contrast, anti-NC-Ig decreased significantly in severe fatigue cases regardless of the elapsed time (4-12 weeks: p = 0.024; beyond 12 weeks: p = 0.005). The incidence of memory impairment was significantly correlated with lower anti-S-Ig levels (-0.359, p < 0.001).Conclusion: The systemic immune response reflected by antibodies to SARS-CoV-2 is strongly correlated with the severity of post-COVID fatigue.
|
|
13. |
- Ulicsni, Viktor, et al.
(författare)
-
Folk knowledge of invertebrates in Central Europe - folk taxonomy, nomenclature, medicinal and other uses, folklore, and nature conservation
- 2016
-
Ingår i: Journal of Ethnobiology and Ethnomedicine. - : Springer Science and Business Media LLC. - 1746-4269. ; 12
-
Tidskriftsartikel (refereegranskat)abstract
- Background: There is scarce information about European folk knowledge of wild invertebrate fauna. We have documented such folk knowledge in three regions, in Romania, Slovakia and Croatia. We provide a list of folk taxa, and discuss folk biological classification and nomenclature, salient features, uses, related proverbs and sayings, and conservation. Methods: We collected data among Hungarian-speaking people practising small-scale, traditional agriculture. We studied "all" invertebrate species (species groups) potentially occurring in the vicinity of the settlements. We used photos, held semi-structured interviews, and conducted picture sorting. Results: We documented 208 invertebrate folk taxa. Many species were known which have, to our knowledge, no economic significance. 36 % of the species were known to at least half of the informants. Knowledge reliability was high, although informants were sometimes prone to exaggeration. 93 % of folk taxa had their own individual names, and 90 % of the taxa were embedded in the folk taxonomy. Twenty four species were of direct use to humans (4 medicinal, 5 consumed, 11 as bait, 2 as playthings). Completely new was the discovery that the honey stomachs of black-coloured carpenter bees (Xylocopa violacea, X. valga) were consumed. 30 taxa were associated with a proverb or used for weather forecasting, or predicting harvests. Conscious ideas about conserving invertebrates only occurred with a few taxa, but informants would generally refrain from harming firebugs (Pyrrhocoris apterus), field crickets (Gryllus campestris) and most butterflies. We did not find any mythical creatures among invertebrate folk taxa. Almost every invertebrate species was regarded as basically harmful. Where possible, they were destroyed or at least regarded as worth eradicating. However, we could find no evidence to suggest any invertebrate species had suffered population loss as a result of conscious destruction. Sometimes knowledge pertaining to the taxa could have more general relevance, and be regarded as folk wisdom concerning the functioning of nature as a whole. Conclusions: The high number of known invertebrate folk taxa suggests that it would be worth conducting further investigations in other areas of Europe.
|
|
14. |
- Ulicsni, Viktor, et al.
(författare)
-
Folk knowledge of non-domestic mammals among ethnic Hungarians in North-Western Romania
- 2013
-
Ingår i: North-Western Journal of Zoology. - 1584-9074 .- 1843-5629. ; 9:2, s. 383-398
-
Tidskriftsartikel (refereegranskat)abstract
- Most ethnobiological research on mammals has focused on the domesticated species and largely ignored the wild taxa. We carried out a research among the ethnic Hungarians in Nusfalau, Romania, to document the local ecological knowledge on mammals. We studied which kinds of local wild mammals the villagers know, which folk taxa they can identify, the names they use for these taxa, and what do they know about the morphological, behavioural and ecological characteristics, as well as the economical impact of these mammals. Twenty persons were interviewed with the aid of colour photographs of 62 mammal species. Five hundred and twenty three individual data on the various folk taxa were thus gathered. The majority of the interviewees were still possessed surprisingly detailed and precise knowledge on the wild species living in their surroundings. They classified the 62 mammal species into 42 folk taxa and grouped them into 11 larger sets. The groupings were almost similar to the scientific classification except for one group which mainly contained mice and voles. The eastern hedgehog (Erinaceus roumanicus) had a unique taxonomy with two highly distinct folk taxa. The characteristics of the known folk taxa were described according to their morphological, ethological-ecological, and cultural salience. In the case of physical appearance, naming of a prototype and comparing to it was typical. In terms of ecological salience of feeding habit, characteristics of movement, habitat, breeding habit, bashfulness, voice, annual and daily pattern of behaviour, and observability were the most important characteristics. The comparison to humans was particularly important when describing behaviour. In terms of cultural salience, the characterization of harm caused and benefit gained was unequivocally dominant. The overwhelming majority of the species were known through personal experience. The effect of books and media was negligible. Local knowledge of wild animals is part of our common European cultural heritage. This knowledge is fading rapidly, and most of it may be lost in the next decades.
|
|
15. |
- Vida, Ádám, et al.
(författare)
-
A Sequence of Phase Transformations and Phases in NiCoFeCrGa High Entropy Alloy
- 2021
-
Ingår i: Materials. - : MDPI. - 1996-1944. ; 14(5):1076
-
Tidskriftsartikel (refereegranskat)abstract
- The present investigation is directed to phase transitions in the equimolar NiCoFeCrGa high entropy alloy, which is a mixture of face-centered cubic (FCC) and body-centered cubic (BCC) crystalline phases. The microstructure of the samples was investigated by using scanning electron microscopy (SEM), time-of-flight secondary ion mass spectroscopy (TOF-SIMS), transmission electron microscopy-based energy-dispersive spectroscopy (EDS) and electron energy loss spectroscopy (EELS), as well as X-ray diffraction (XRD) measurements. Based on the phases observed in different temperature ranges, a sequence of the phase transitions can be established, showing that in a realistic process, when freely cooling the sample with the furnace from high to room temperature, a microstructure having spinodal-like decomposition can also be expected. The elemental mapping and magnetic behaviors of this decomposed structure are also studied.
|
|
16. |
- Vida, Adam, et al.
(författare)
-
Evolution of the phase structure after different heat treatments in NiCoFeCrGa high entropy alloy
- 2018
-
Ingår i: Journal of Alloys and Compounds. - : Elsevier. - 0925-8388 .- 1873-4669. ; 743, s. 234-239
-
Tidskriftsartikel (refereegranskat)abstract
- The non-equilibrium nature of a two-phase NiCoFeCrGa high entropy alloy (HEA) is studied by analyzing its microstructures after different heat-treatment conditions. The microstructure - containing a mixture of well-separated FCC and BCC regions - of the as-cast alloy has changed strongly by heat-treatment for 1 h at 1150 K, significantly changing the ratio of the volume fraction of the FCC and BCC phases. Needle like BCC phase particles evolved inside the original FCC regions when cooling the heat-treated samples to room temperature by rapid or medium rates. In the case of slow cooling, the original BCC regions transformed into a mixture of a matrix and cube-like BCC phase precipitates, which can be attributed to the effect of the transition between para-and ferromagnetism around the Curie-point. There is also an unambiguous correlation between the cooling rate and mechanical properties of the heat-treated alloys.
|
|
17. |
- Zsolt, Benko, et al.
(författare)
-
Triassic fluid mobilization and epigenetic lead-zinc sulphide mineralization in the Transdanubian shear zone (Pannonian basin, Hungary)
- 2014
-
Ingår i: Geologica Carpathica. - Geological institute of the Slovak Academy of Science. - 1335-0552 .- 1336-8052. ; 65, s. 177-194
-
Tidskriftsartikel (refereegranskat)abstract
- A combined fluid inclusion, fluid inclusion plane, lead isotope and K/Ar radiometric age dating work has been carried out on two lead-zinc mineralizations situated along the Periadriatic-Balaton Lineament in the central part of the Pannonian Basin, in order to reveal their age and genetics as well as temporal-spatial relationships to other lead-zinc fluorite mineralization in the Alp-Carpathian region. According to fluid inclusion studies, the formation of the quartz fluorite-galena-sphalerite veins in the Velence Mts is the result of mixing of low (0—12 NaCl equiv. wt. %) and high salinity (10—26 CaCl2 equiv. wt. %) brines. Well-crystallized (R3-type) illite associated with the mineralized hydrothermal veins indicates that the maximum temperature of the hydrothermal fluids could have been around 250 °C. K/Ar radiometric ages of illite, separated from the hydrothermal veins provided ages of 209—232 Ma, supporting the Mid- to Late-Triassic age of the hydrothermal fluid flow. Fluid inclusion plane studies have revealed that hydrothermal circulation was regional in the granite, but more intensive around the mineralized zones. Lead isotope signatures of hydrothermal veins in the Velence Mts (206Pb/204Pb = 18.278—18.363, 207Pb/204Pb = 15.622—15.690 and 208Pb/204Pb = 38.439—38.587) and in Szabadbattyán (206Pb/204Pb = 18.286—18.348, 207Pb/204Pb = 15.667—15.736 and 208Pb/204Pb = 38.552—38.781) form a tight cluster indicating similar, upper crustal source of the lead in the two mineralizations. The nature of mineralizing fluids, age of the fluid flow, as well as lead isotopic signatures of ore minerals point towards a genetic link between epigenetic carbonate-hosted stratiform-stratabound Alpine-type lead-zinc-fluorite deposits in the Southern and Eastern Alps and the studied deposits in the Velence Mts and at Szabadbattyán. In spite of the differences in host rocks and the depth of the ore precipitation, it is suggested that the studied deposits along the Periadriatic-Balaton Lineament in the Pannonian Basin and in the Alps belong to the same regional scale fluid flow system, which developed during the advanced stage of the opening of the Neo-Tethys Ocean. The common origin and ore formation process is more evident considering results of large-scale palinspastic reconstructions. These suggest, that the studied deposits in the central part of the Pannonian Basin were located in a zone between the Eastern and Southern Alps until the Early Paleogene and were emplaced to their current location due to northeastward escape of large crustal blocks from the Alpine collision zone.
|
|